A woman with ties to a right-wing activist group falsely claimed to The Washington Post that she had conceived a child with Roy S. Moore, the Republican Senate candidate in Alabama, when she was 15, the newspaper reported on Monday afternoon.

The woman, identified by the paper as Jaime T. Phillips, claimed in recent interviews with reporters that she had an abortion after having sex with Mr. Moore in 1992. But The Post said that it had discovered inconsistencies in her account and evidence that the woman concocted the sensational claim to try to dupe reporters and coax them into discussing the political impact her story could have on Mr. Moore.

A reporter with The Post confronted the woman about the holes in her story on Wednesday and then Post journalists saw her on Monday morning entering the offices of Project Veritas, a conservative group that films undercover videos. The organization, led by the activist James O. Keefe, has recently targeted journalists, trying to goad them into revealing biases or unethical schemes to discredit the news media.

“The intent by Project Veritas clearly was to publicize the conversation if we fell for the trap,” Martin Baron, the executive editor at The Post, was quoted as saying. “Because of our customary journalistic rigor, we weren’t fooled.”

A reporter and a videographer with The Post questioned Mr. O’Keefe on Monday outside his group’s office in Mamaroneck, N.Y., about Ms. Phillips’s apparent connections with Project Veritas.

“I am not doing an interview right now, so I’m not going to say a word,” Mr. O’Keefe responded.

Ms. Phillips first contacted The Post in a mysterious email on Nov. 9, the newspaper reported. It was sent just hours after the newspaper had published a story about Leigh Corfman, who said she was 14 years old when Mr. Moore, then 32, engaged in a sexual encounter with her. “Roy Moore in Alabama,’’ the email to a Post reporter read, according to the story. “I might know something but I need to keep myself safe.”

A reporter at The Post interviewed Ms. Phillips again on Wednesday at a restaurant in Virginia. In that interview, which was partly recorded on video by The Post, the reporter pressed Ms. Phillips about apparent inaccuracies in her past work experiences and about why she had decided to contact the newspaper. The woman then said she no longer wanted to participate in the story.

While researching the woman’s account, The Post found a GoFundMe fund-raising page under the same name as the woman. That woman said she was moving to New York for a new job. “I’ve accepted a job to work in the conservative media movement to combat the lies and deceipt of the liberal MSM,” the page said, according to The Post. “I’ll be using my skills as a researcher and fact-checker to help our movement.”

The apparent elaborate effort to dupe The Post into publishing false claims about Mr. Moore follows similar schemes to discredit the newspaper and other news media. Mr. Moore has denied all allegations of sexual misconduct., and a campaign official called the claims “a fabricated November surprise.”

In one effort to undermine the stories, a man called an unknown number of people in Alabama claiming to be reporter with The Post and offered up to $7,000 if they were “willing to make damaging remarks” about Mr. Moore. Some of his supporters have also tried to smear a Post reporter involved in the first story about Mr. Moore, and the Moore campaign also created a website to “report inappropriate news organization contact.”

After The Post published its article about Ms. Phillips on Monday, Mr. O’Keefe said he would respond with his own video about the newspaper. “They are scared,” he said.

Last month, Project Veritas released videos featuring journalists at The New York Times. In one undercover video, a junior Times editor discussed his political beliefs and mocked the idea of objective reporting. After its release, a spokeswoman at The Times said that a “recent hire in a junior position violated our ethical standards and misrepresented his role.”